Problem overlapping two meshes for baking
ALT+G clears location of any mesh. so it brings mesh to origin(0,0,0).
similarly Alt+s to clear scale and Alt+R to clear rotation.

The two meshes are different, resulting different center of masses (geometrical origins) one of the meshs center of mass may be higher, so even if you clear location i.e set to origin they are not quite over-lapping.

In order to correct it, select all bottom vertices of anvil ( easy in wire mode ) shft+s-> cursor to selection then tab out to object mode shift+alt+cltr+c change origin to 3d cursor. Do same for two meshes.

Then press Alt+G the should be overlapping. In fact Andrew specifically mentioned these in previous videos.